In the packaging industry, the production of boxes is carried out in line, by folding and gluing cardboard blanks using machines which are called folder-gluers. A folder-gluer comprises a series of modules and stations, each comprising functional arrangements. The number of modules varies in accordance with the complexity of the production operations which the type of box selected requires. The folder-gluer is provided with a feeder which supplies the machine blank by blank from a stack, an alignment module, a breaker which pre-breaks the non-longitudinal folds, folders with hooks which fold the front lugs and then the rear lugs of the blank, a gluing station, a folder for folding the longitudinal folds of the blank, a presser which compresses all of the folds and deposits the boxes in a shingle stream, and a delivery module which receives the boxes while maintaining them in a pressed state in order to allow the glue to dry.
The conveying of the blanks from one station to another according to a trajectory which is substantially planar and horizontal is carried out using belt type conveyors which, by means of friction, grip the blanks between a lower conveyor and an upper conveyor. The lower conveyor is provided with lower belts and the upper conveyor is provided either with upper belts or with upper support rollers.
In order to comply with specific regulations in terms of information which is intended for visually impaired or blind persons, it has become necessary to print some messages in Braille characters on some packaging boxes, in particular on medication boxes. The Braille characters are embossed on a surface of the box in order to cause dots to appear in relief or protuberances which enable tactile reading of the messages.
The embossing of the Braille characters is carried out using a device which is mounted in an embossing module, installed in the folder-gluer. The device comprises two rotating embossing tools, a male embossing tool which cooperates with a female embossing tool, which tools are respectively mounted at respective opposite sides of the plane defined by the travel of the blanks in accordance with their trajectory.
The ease and rapidity with which a visually impaired or blind person reads the embossed message is dependent on the size, shape and regularity of the Braille characters which are located on the surface of the box. The Braille characters must be embossed without burrs and have a predetermined height. The quality of the box obtained in this manner is also dependent on the quality of the embossing of the Braille characters.